JPS6246702A - Rear axle housing - Google Patents

Abstract

PURPOSE:To eliminate large casing frame while to shorten the welding length by integrally casting annular steel members at the opposite ends of spherical graphite cast axle housing then welding a steel axle to said steel members. CONSTITUTION:When casting a spherical graphite cast iron axle housing 1, annular steel members 4, 5 are casted integrally at the opposite ends 2, 3. Upon finish of required machining onto said axle housing 1, steel axle tubes 6, 7 are fusion welded to the steel members 4, 5 at the opposite ends then mechanical machining is performd. With such manufacturing method, productionability of axle housing is improved, the cost can be reduced and the quality can be improved.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、車両用のリヤアクスルハウジングに関するも
のである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rear axle housing for a vehicle.

〔従来の技術〕[Conventional technology]

従来から用いられているリヤアクスルハウジングは、板
金溶接構造のものと、一体鋳造構造のものとに大別する
ことができる。Conventionally used rear axle housings can be roughly divided into those having a sheet metal welded structure and those having an integral casting structure.

すなわち、中型、小型車用のリヤアクスルハウジングは
、自動車用熱間圧延鋼板をプレスにて所望形状に成形し
た数個の部品を融接にて接合した構造のものが多く用い
られている。That is, rear axle housings for medium-sized and small-sized vehicles often have a structure in which several parts are formed by press-forming hot-rolled automotive steel sheets into a desired shape and are joined by fusion welding.

一方、トラック、トラクター、クレーン車など大型車用
のリヤアクスルハウジングには一体鋳造のものが比較的
多く使用されている。On the other hand, monolithic cast housings are relatively often used for rear axle housings for large vehicles such as trucks, tractors, and crane vehicles.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

前者の板金溶接構造では、プレス工数、あるいは溶接工
数が増大するばかりでなく、長い範囲にわたる溶接部の
品質を完全に保証することは技術的にきわめて困難であ
る。また実体の強度試験を実施すると溶接箇所が破断す
ることをしばしば経験するものである。In the former sheet metal welded structure, not only does the number of press steps or welding steps increase, but it is technically extremely difficult to completely guarantee the quality of the weld over a long range. Furthermore, when conducting strength tests on actual objects, it is often experienced that welded parts break.

後者の一体鋳造では、材質として鋳鋼品が多く用いられ
ているが、最近では球状黒鉛鋳鉄の強度、靭性面の改善
が進み、鋳鋼と比べ原価的に安価な球状黒鉛鋳鉄も使用
されるようになってきた。In the latter type of monolithic casting, cast steel is often used as a material, but recently the strength and toughness of spheroidal graphite cast iron have been improved, and spheroidal graphite cast iron, which is cheaper than cast steel, is also being used. It has become.

しかし、いずれの場合も鋳造に際し長尺の大きな鋳枠が
必要であるほか、造型時間の増大など生産性の向上を阻
害する要因を含むものである。However, in both cases, a long and large casting flask is required for casting, and there are factors that impede productivity improvement, such as an increase in molding time.

また、球状黒鉛鋳鉄製の場合、アクスルハウジング本体
部とアクスルチューブ部の一体鋳造では、アクスルチュ
ーブ部の強度不足をきたすことがしばしばあり、設計上
の大きな制約となっている。Furthermore, in the case of spheroidal graphite cast iron, integral casting of the axle housing body and axle tube often results in insufficient strength of the axle tube, which is a major design constraint.

そこで、これらを別体とし、球状黒鉛鋳鉄製アクスルハ
ウジング本体部と鋼製アクスルチューブ部を溶接接合す
ることが考えられるが、球状黒鉛鋳鉄と鋼の溶接は溶接
部にセメンタイトが析出し易く、現在の技術ではほとん
ど強度保証し難いという問題がある。Therefore, it is conceivable to separate these parts and weld the axle housing body made of spheroidal graphite cast iron and the axle tube part made of steel, but welding of spheroidal graphite cast iron and steel tends to cause cementite to precipitate in the weld, and currently The problem with this technology is that it is difficult to guarantee strength.

つまり、これらはすべて鋳鉄と鋼材との融接箇所の信頼
性が乏しいために起因するものであり、本発明者は、こ
れらの欠点を解消し得る新規な技術を開発したものであ
る。In other words, all of these problems are caused by the poor reliability of the fusion weld between cast iron and steel, and the present inventor has developed a new technique that can eliminate these drawbacks.

本発明の目的は、大型の鋳枠を必要とせず、また溶接長
さを縮減し、しかも生産性と品質を著しく向上し得るリ
ヤアクスルハウジングを提供するものである。An object of the present invention is to provide a rear axle housing that does not require a large casting flask, reduces welding length, and can significantly improve productivity and quality.

〔問題点を解決するための手段〕 本発明のリヤアクスルハウジングは、球状黒鉛鋳鉄製ア
クスルハウジングの両端に環状の鋼材を鋳包みにて一体
に成形し、該鋼材に鋼製のアクスルチューブを融接した
ものである。[Means for Solving the Problems] The rear axle housing of the present invention is produced by integrally molding an annular steel material at both ends of an axle housing made of spheroidal graphite cast iron by casting, and then fusion-welding a steel axle tube to the steel material. This is what I did.

〔実施例〕〔Example〕

以下本発明の実施例を図面に基いてさらに詳細に説明す
る。第１図は本発明によるリヤアクスルハウジングの縦
断面図である。Embodiments of the present invention will be described in more detail below with reference to the drawings. FIG. 1 is a longitudinal sectional view of a rear axle housing according to the present invention.

球状黒鉛鋳鉄製のアクスルハウジング１を鋳造するとき
、両端部２，３に環状の鋼材４，５を鋳包み一体に成形
する。When an axle housing 1 made of spheroidal graphite cast iron is cast, annular steel members 4 and 5 are cast-in and integrally formed at both ends 2 and 3.

このアクスルハウジング１は公知の必要な工程を経た後
、両端の鋼材４，５に鋼製のアクスルチューブ６．７を
融接し、機械加工して完成するものである。This axle housing 1 is completed by fusion welding a steel axle tube 6.7 to the steel members 4 and 5 at both ends and machining the same after undergoing necessary known steps.

第２〜４図は、鋳包み部分の断面形状を示すものでアク
スルハウジングを形成する球状黒鉛鋳鉄１の溶湯と鋼材
４，５の接合面積及び鋼材４，５とアクスルチューブ６
．７との接合面積を、その負荷荷重に応じて任意に選定
することができる。Figures 2 to 4 show the cross-sectional shape of the cast-in part, and show the joint area between the molten spheroidal graphite cast iron 1 and the steel materials 4 and 5 that form the axle housing, and the joint area between the steel materials 4 and 5 and the axle tube 6.
．． The joint area with 7 can be arbitrarily selected depending on the applied load.

従って、理想的な最適設計が可能となる。Therefore, ideal optimal design is possible.

〔発明の効果〕〔Effect of the invention〕

本発明によるリヤアクスルハウジングが有する特長を列
記すると下記の通りである。The features of the rear axle housing according to the present invention are listed below.

１）アクスルハウジング１と鋼材４，５とは、峙包みに
よって強固に固着されている。1) The axle housing 1 and the steel materials 4 and 5 are firmly fixed by facing each other.

２）鋼材４，５とｍ製のアクスルチューブ６．７とは共
に同材であるため、強固に融接されている。2) Since the steel materials 4 and 5 and the axle tube 6.7 made of M are both made of the same material, they are firmly fusion welded.

３）この融接部は接合長さが著しく短いので作業能率が
向上する。3) Since this fusion weld has a significantly short joining length, work efficiency is improved.

４）球状黒鉛鋳鉄製のアクスルハウジング１を鋳造する
際、大型の鋳枠を使用する必要がないため生産性を低下
させることはない。4) When casting the axle housing 1 made of spheroidal graphite cast iron, there is no need to use a large casting flask, so productivity is not reduced.

５）アクスルチューブ部に所望の強度の鋼材を使用する
ことができる。5) A steel material with desired strength can be used for the axle tube portion.

以上の説明で明らかなように、本発明のリヤアクスルハ
ウジングは、生産性の向上、原価低減、品質向上など多
くの優れた効果を有するものである。As is clear from the above description, the rear axle housing of the present invention has many excellent effects such as improved productivity, reduced cost, and improved quality.

【図面の簡単な説明】[Brief explanation of drawings]

第１図はリヤアクスルハウジングの縦断面図、第２〜４
図はともに鋳包み部の断面図である。Figure 1 is a longitudinal sectional view of the rear axle housing, Figures 2 to 4
Both figures are cross-sectional views of the cast-in part.

Claims (1)

【特許請求の範囲】[Claims] 球状黒鉛鋳鉄製アクスルハウジングの両端に環状の鋼材
を鋳包みにて一体に成形し、該鋼材に鋼製のアクスルチ
ューブを融接したことを特徴とするリヤアクスルハウジ
ング。A rear axle housing characterized in that an annular steel material is cast-in integrally formed at both ends of an axle housing made of spheroidal graphite cast iron, and a steel axle tube is fusion-welded to the steel material.